The demolition of City Center in 2009, Columbus's downtown shopping mall, is certainly the biggest change that has happened since we moved away. I remember when the mall was built in 1989. It was really big deal. Since Lex Wexner resides in Columbus Ohio, it of course had all the limited brand stores, including his recent acquisition an Henri Bendel. I still have a skirt I got there, which was probably deeply discounted, that I will likely never get rid of for nostalgia's sake. (A lot of development in Columbus involves Lex Wexner, they are currently building the Wexner Medical Center at Ohio State, for example.) The mall was in a state of decline for a long time, mainly due to the fact that several larger, suburban malls were constructed. City Center could no longer draw suburbanites into the somewhat neglected downtown.
Shortly after the demolition was proposed, there was a plan to develop the site for a housing project. It looks like there has been some attempt to get some housing downtown since with left, with a few tower projects nearby. But in the end they have turned it into a large park called the "Columbus Commons." It has a carousel and amphitheater; both feel a bit small for such a large site. Also, unlike many good urban parks, the buildings surrounding the site are not much to look at. In the picture above you can see the old, no longer open, Lazarus Department store building. Either side of the park in the other direction has a view of parking garages. Occasionally there's still signage from the mall, and the covered connector space next to the Ohio Theater was maintained. Now it will take you between the Commons and the State House lawn.
Still, The official grand opening is later this month, and it could be nice to have a downtown event space in the summer.